Art of electrotyping.



M. A. MoKEE.

ART 0F ELBGTROTYPING.

ANLIOATION FILED Nov. 19. 1910.

1,083,435. Patented July 23,1912.

MILTON MCKEE, OF W'ESTEELY, RHODE ISLAND, ASSIGNOR TO C. B. COTTRELL & i

SONS COMPANY, OF NEW YORK, N. Y., A CORPORATION OF NEW JERSEY.

ART OF ELECTROTYPING.

Specification of Letters Patent.

Patented July 23, 1912.

Applicatonpled November 19, 1910. Serial No. 593,269.

To all whom it may concern: A

Be it known that I, MILTON MoKnn, a citizen of the United States. and resident of lVesterly, in the county of lllashington and State of Rhode Island, have invented a new and useful Improvement in the Art of Elec-- portions of the plate for strengthening the. plate at these points.

In the accompanying drawings, Figure 1 illustrates an ordinary electro deposit bath tank in section, Fig. 2 is a face view of a mold after a thin coating of copper has been applied thereto in the bath, Fig. 3 is a longitudinal section taken in the plane of the line A-A of Fig. 2, looking in the direction of the arrows, Fig. 4 is a face View of the mold after a coating has been applied thereto on that portion upon which no `further deposit of copper is desired, Fig. 5 is a lon'- gitudinal section through the same in the plane of the line B-B of Fig. 4', looking in the direction of the arrows, Fig. 6 is a similar section showing the mold after the same has been subjected to a furthertreatment in the bath tank for depositing an additional amount of copper on the back` of the raised or printing surface of the shell, Fig. 7 is a view of the printing face o f the completed plate, and Fig. 8 is a longitudinal section taken in the plane `ofthe line C-C of Fig. 7

looking in the direction of the arrows showing theplate provided with the usual iilling.

In carrying out my improved process of forming electrotype plates, the mold l on its board 2 is first immersed in the liquid 3, contained`by the bath tank 4, a sufficient time to permit the deposit of copper coating of a desired thickness thereon.` The mold is then removed from its bath and those portions of the shell 5 upon which it isV desired to prevent a further deposit of copper are coated with a deposit resisting material 6, such, for instance, as lithographers ink. The mold, with its partially completed shell 5, is then again immersed in the liquid bath 3 and a further deposit of the copper is permitted on the uncoated portions of the shell which, in

thepresent instance, would be upon the backs or under the raised or printing portions of the plate. After a requisite amount of copper has been deposited on these uncoated portions of the shell', the mold is again removed from its liquid bath and the shell removed in the lusual manner from the mold. The back of the shell may then be provided with the usual metal backing or filling 7'.

In a. plate formed according to this present invention, the low portions of the plate which make no printing impression may be made very thin and thus effect a large saving of copper while the portions which are to make the printing impression may be made much thicker and stronger, thus providing a firmer body strain.

What I claim is: 1. The process of forming electrotype plates comprising depositing the copper in one step onto the mold uniformly and depositing additional copper in a subsequent step into the backs of the printing portions of the shell being formed. n

2. The process of forming electrotype plates consisting in depositing the copper onto the mold to a required thickness', then applying a coat of deposit resisting material onto those portions of the shell to be left at for the impression such thickness and finally depositing an additional amount of copper onto the unprotected portions of the shell.

`3. The process of forming electrotype plates consisting in depositing the copper onto the mold to a required thickness, then applying a coatof deposit resisting material onto the expose'dbaclr of the shell at the raised portions which are to be the low portionsvof the shell v4and then depositing the copper to the desired thickness onto the eX- posed back of the shell at the uncoated porportions of the finished plate.

In testimony, t-hatI claim the foregoing as my invention, I have signed my name in vtions which are to be the high or printing presence of two witnesses, this 16th'day `of November 1910.

MILTON A. MCKEE.

Witnesses:

F. GEORGE BARRY, HENRY C. THIEME. 

